It is becoming increasingly common to have a number of user devices within a home that are each arranged to access the internet. For example, a typical home may include one or more desktop computers, one or more laptops, PDAs, smartphones and so on. Such devices will usually access the internet via a home network, particularly by connecting to a residential gateway.
Residential gateways are home networking devices used to connect devices to a Wide Area Network (WAN) such as the internet. The term “residential gateway” refers to the connection device between a home network and the WAN and may comprise one or more of a modem, such as a DSL (Digital Subscriber Line), ADSL (Asymmetric Digital Subscriber Line) or cable modem, a network switch, a router and a wireless access point if providing wireless access.
A typical arrangement is shown in FIG. 1. Here, a number of different devices including a home PC 101, a mobile phone 102 and a laptop 103 are connected to the internet 104 via a home gateway 105. The home gateway has a modem 106 and a router 107 that routes data packets between the various connected devices 101, 102, 103 and the modem, allowing the devices to share a common internet connection. When a data packet is sent by a connected device such as laptop 103 to a destination address over internet 104 the router removes the local IP source address from the packet and stores it in a table, Network Address Translation (NAT) table 108. The router also replaces the IP source address in the packet with the external IP address of the router/home gateway, inserts the destination IP address of the packet into the NAT table and associates it with the local IP address of the local device. When a response packet is received from the destination device over the internet the router determines the source IP address found in the header of the incoming packet and correlates this with the destination IP address stored in the NAT table. As a result, the router determines the associated local IP address and forwards the packet to the appropriate local IP address such that it reaches the appropriate local user device such as laptop 103. In this way multiple local user devices with local IP addresses can share a common external IP address and communicate over the internet.
With such a large number of different devices accessing the internet within a home via a common connection it is becoming increasingly difficult for parents to monitor and police the content that their children are consuming from the internet. Previous attempts to control or monitor accessed content have relied upon hardware or software firewalls to restrict content, or monitoring programs to track the websites visited by a user or a user device. Programs or hardware that restricts internet access often rely on a pre-approved list of website addresses that are safe to visit and may be overly restrictive. Monitoring programs only allow the parent to check visited websites after the event. These types of restriction and monitoring methods do not present the monitoring party (i.e. the parent or authority) with real time monitoring of accessed content at a location that is likely to be viewed until after the access, or attempted access, has occurred.
There is a need for a way of monitoring content being consumed by network users within a home network preferably that can be easily accessed by a responsible party and that will not drain computing resources unnecessarily.